Biceps have always been the most desired muscle in the body. From "pumping iron" days with Arnold Schwarzenegger to the latest blockbuster, biceps signify strength and power. You can even find the person with the "biggest biceps" name in the Guinness Book of Records.
The biceps attach to the radius, and the one head attaches to the caracoid process and the other to the glenoid. The biceps have two muscle bellies lying side by side on the front of the arm, thus the name biceps. Although the muscle bellies attach at two different points on the shoulder blade, they are joined at the distal end by a common tendon of insertion. This tendon weaves between the two bones of the forearm. The biceps is one of three muscles responsible for flexing the elbow against resistance. It is impossible to totally isolate the biceps from the other two elbow flexors (brachioradialis and brachialis), but it is believed that the biceps can be emphasised by maintaining a supinated grip during resisted elbow flexion. The other action of the biceps is supination.
Training the Biceps
It is important to maintain a supinated grip during elbow flexion. A neutral or pronated grip emphasizes the other two elbow flexors, as the biceps become mechanically weaker.
When performing a barbell curl, the first concern is to determine the grip width on the bar. Traditionally we are taught to use a "shoulder width grip." Now if you have ever attempted this on a regular basis and with considerable weight, you may have detected a sensation that, for lack of a better term, described as "shin splint" type pain deep within the wrist of the forearms.
This is due to the fact a shoulder width grip on a straight bar violates a key aspect of the skeletal anatomy … the carrying angle. If you stand in front of a mirror with your arms at your sides and fully supinated you will notice that, your hands do not hang at shoulder width.
This lateral angle that appears at the elbow (outward bend of the forearm) is the carrying angle.
Allowing for the carrying angle usually results in a grip that is only an inch or two wider than shoulder width. If you look in the mirror and it appears that your hands are eight inches wider than you shoulders, you may need to check the position of your upper arm. Did you turn your entire arm outward instead of just supinating?
Once you have the bar in hand, the key is to define the correct path of motion. Traditionally instructions only make reference to the motion of the bar. Curl the bar up to your chin and back down. This overly simplistic is actually misdirected teaching, leads to the two major mistakes that ultimately defeat bicep lovers everywhere:
- Shoulder extension to help initiate the movement
- Shoulder flexion to help finish the movement.
The result … less biceps involvement and more shoulder work. To emphasize the biceps the shoulders have to be stabilised and the only joint moving is the elbows. It should go without saying that if you sway at the hips or in the back in an attempt to move the weight, you have defeated the purpose and increased the risk.
Performing curls unilaterally with dumbbells alleviates the carrying angle concern. Variations in shoulder position can also be used by doing seated incline curls or concentration curls. An extreme shoulder flexed position de-emphasizes the biceps due to slack in the bicep.
It is common to see people twisting the dumbbells as they near full extension. This actually emphasises the brachioradialis at the start and the biceps is not brought fully into action until full supination is achieved.
Barbell Precher Curls
If the humerus is taken significantly out of the vertical position (precher curl), the direction of resistance may need to be altered with a cable to prevent loss of resistance due to balance through the joint (balance is when the resistance falls through a joint. There is not tension at this point).
When using machines, it is important to line up your elbow with the axis of the machine. Poor construction may not allow you to do this well. It is also important to note that the cam on certain machines allow for maximum resistance when the bicep is at its’ weakest point in the range. This is at either the top or bottom of the movement.
Some Common Myths
- Work One Head vs the Other. It is believed that varying you grip width on a bar will work different heads of the biceps. This is untrue due to the biceps common tendon of insertion, and the fact that the elbow is a hinge joint, their ability to be emphasised separately is inconsequential.
- Hammer Curls. When performing elbow flexion in a neutral grip (hammer curl) the brachioradialis is emphasized due to the fact that the biceps are mechanically weaker.
- Bar to Chin. The only way to touch the chin is by moving the shoulder into flexion. This decreases the effort of the biceps. Full range of motion in barbell curls is achieved by simply bringing the forearm as close to the upper arm/biceps as possible without moving the upper arm in any direction.
- Barbell Curls are for Mass. There is no such thing as a mass building or shaping exercise. The barbell curl is often thought of as a mass builder because of the amount of weight used. This is often because of "cheating" that you can barbell curl more weight than other bicep exercises. Any exercise emphasising the biceps will aid in mass development if it is performed correctly.
- EZ Curls are Great for Biceps. Using an EZ curl bar allows a more comfortable grip, but remember, maintaining full supination is the key if your goal is truly biceps emphasis. EZ curl bars also offer limited options for hand placement.
- Dumbbells are for Shaping.
- Precher Curls will "Fill the Gap".
- Concentration Curls are for the Peak.
Actually, you could kill these last three with one stone. The truth is, barring traumatic injury or surgical intervention, the shape of a muscle is genetically predetermined. When a muscle gets bigger, it obviously changes in appearance, but its final shape is not up to you or your exercise selection. The amount of fibers you are "allotted" and their distribution, the influence of the fascial envelope or covering of each muscle have much to do with this. Think about it. In all the years of bodybuilding, have you ever seen anyone with Arnold shaped biceps one year and then, due to exercise selection, display Franco shaped biceps the next year (or even the next decade). Wake up!
The gap or space between your elbow and your biceps belly is your bicep tendon. No exercise can alter the tendon to muscle belly length ratio. Therefore, this gap cannot be "filled," so to speak.
Concentration curls are performed in the shoulder-flexed position. Since the biceps is a two joint muscle crossing the elbow and shoulder, its final length when contracted is only partially determined by elbow flexion/range of motion. So it’s the position of the shoulder joint allowing the biceps to contract to near its shortest position that creates this appearance.